Russian ruble rattled by renewed Ukraine unrest

The Russian ruble has declined by roughly 9% versus the U.S. dollar since the start of 2014.

International markets were roiled Monday and the Russian currency hit a three-week low as traders and investors worry about renewed tensions between Russia and Ukraine.

The ruble declined by roughly 0.7% Monday versus the U.S. dollar -- not far from the lows seen in mid-March. Russia's main stock market index also dipped by nearly 2% before recovering slightly. The Russian Micex index has declined by more than 10% since the start of the year.

Ukraine and western nations are accusing Russia of deliberately trying to destabilize parts of eastern Ukraine ahead of national elections in late May. Russia's foreign minister Sergey Lavrov denied that Russian forces were active in the east.

Western nations, in an attempt to protect Ukraine and punish Russia, have issued sanctions against some individuals and firms responsible for the unrest.

British foreign secretary William Hague said more sanctions may be needed.

"Further sanctions have to be the response to Russia's behavior," Hague said Monday at a meeting of European Union foreign ministers in Luxembourg. Hague said the ministers would need to negotiate "much more far-reaching" punishments against Moscow.